CVE-2026-90913: CWE-284 Improper Access Control in Joomla! Project Joomla! CMS
Joomla! Core - [20260903] - Core - Improper ACL checks for access level webservice endpoints in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - An improper access check allows unauthorized users to perform mutation actions in access level endpoints.
AI Analysis
Technical Summary
Joomla! CMS versions 4.0.0 to 5.4.8 and 6.0.0 to 6.1.3 contain an improper access control vulnerability in the core webservice endpoints that manage access levels. Due to insufficient ACL checks, unauthorized users with elevated privileges can perform mutation actions on these endpoints, potentially altering access controls improperly. The CVSS v4.0 score is 7.0, indicating a high severity issue. There is no information about available patches or vendor advisories specifying remediation status.
Potential Impact
The vulnerability allows unauthorized users with certain privileges to perform mutation actions on access level endpoints, potentially leading to unauthorized changes in access control configurations. This could result in privilege escalation or unauthorized access to protected resources within Joomla! CMS instances running affected versions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to Joomla! CMS webservice endpoints to trusted users only and monitor for unusual activity related to access level modifications.
CVE-2026-90913: CWE-284 Improper Access Control in Joomla! Project Joomla! CMS
Description
Joomla! Core - [20260903] - Core - Improper ACL checks for access level webservice endpoints in Joomla 4.0.0-5.4.8, 6.0.0-6.1.3 - An improper access check allows unauthorized users to perform mutation actions in access level endpoints.
CVSS v4.0
Score 7.0high
Affected software
Joomla! Project
Joomla! CMS
pkg:composer/joomla/joomla-cmsRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Joomla! CMS versions 4.0.0 to 5.4.8 and 6.0.0 to 6.1.3 contain an improper access control vulnerability in the core webservice endpoints that manage access levels. Due to insufficient ACL checks, unauthorized users with elevated privileges can perform mutation actions on these endpoints, potentially altering access controls improperly. The CVSS v4.0 score is 7.0, indicating a high severity issue. There is no information about available patches or vendor advisories specifying remediation status.
Potential Impact
The vulnerability allows unauthorized users with certain privileges to perform mutation actions on access level endpoints, potentially leading to unauthorized changes in access control configurations. This could result in privilege escalation or unauthorized access to protected resources within Joomla! CMS instances running affected versions.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to Joomla! CMS webservice endpoints to trusted users only and monitor for unusual activity related to access level modifications.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Joomla
- Date Reserved
- 2026-09-14T11:03:59.812Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6abbeaabe94738e05c4dd18b
Added to database: 09/29/2026, 16:43:23 UTC
Last enriched: 09/29/2026, 16:57:05 UTC
Last updated: 09/29/2026, 18:20:12 UTC
Views: 6
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